Hosiery run inhibiting preparation



F. F. LINDSTEDT HOSIERY RUN INHIBITING PREPARATION Filed May 12, 1944 E' 'Il aienied Sept. i

l STATES ATNT oFFlcE 4 Claims.

The invention relates to sheer knitted textilel materials and preparations used therein for improving the quality and wearing characteristics of such textiles and relates more particularly to a run inhibiting preparation for sheer hosiery. This application is a continuation-impart of my copending application, Serial No. 279,465, filed June 13, 1941.

An object of the present invention is to provide a composition of matter which may be applied to sheer knitted hosiery either in the form of a rinsing preparation or applied to the hosiery during its manufacture, as for example in the dye baths, or incorporated in synthetic materials from which articial silk threads are formed, and which will function to inhibit the unraveling of the knitted stitches upon breaking of a thread in the knitted network of the fabric.

Another object of the invention is to provide a composition of the character above which when applied to hosiery, will be substantially undetectable and will leave the hosiery soft and delicate, and will at the same time increase and improve the sheerness of the hosiery.

Still another object of the invention is to provide a composition of the character above which will substantially improve the resistance of sheer silk hosiery to snagging when drawn or moved across rough surfaces.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It

is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth in the claims.

Referring to said drawing:

Figure 1 is a fragmentary plan view of the knitted construction of sheer hosiery to which the present invention pertains, the hosiery portion shown being greatly enlarged in view of clarity.

Figures 2, 3 and 4 are plan view of a pair of engaged loops of the hosiery and illustrate the successive stages in the slipping of one loop out of the embrace of the other.

Figures 5, 6 and 7 are cross-sectional view taken respectively on the planes of lines 5 5, 6 6 and 1 1 of Figures 2, 3 and 4.

Figure 8 is a vertical longitudinal sectional view of hosiery testing apparatus.

(Cl. 10G-219) Figure 9 is a plan view of an end of the apparatus illustrated in Figure 8.

As will be understood, fine sheer hosiery is made from a knitted fabric and as illustrated in Figure 1 of the drawing, is usually composed of a series of loops hung in rows one upon the other and constructed from the curvings of a single thread which runs continuously through the fabric. One set of loops is formed on the preceding row and any particular loop or stitch is dependent for its support on neighboring stitches above, below and on either side of it. Thus if the thread becomes severed at any point, the loops around such point lose contact with each other and a considerable opening is incurred and which, due to the release of successive loops, generally forms a so-called run or elongated opening of the stitches. I.have found that by applying to the fabric a composition which will increase the coelcient of friction between the loops, the slippage of one loop out of the grasp of another may be resisted and inhibited to an extent where a run may be checked and prevented at the point of severing of the thread, leaving therefore only a small inconspicuousr opening in the knitted fabric. In providing such a composition it Will of course be clear thatl no gluing or sticking of the stitches together is permissible, for such action would immediately render the fabric relatively stiff and undesirable. It is a feature of the present invention to provide a composition which leaves the loops completely free for movement; relative to each other. whereby the soft and delicate texture of the sheer hosiery is not impaired.

It is also necessary that the composition applied will not substantially increase the coeilicient of friction of the hosiery to their objects, as such action would interfere with the comfort of the wearer and also provide an undesirable rubbing action against other dress materials worn adjacent to the hosiery. As a feature of the present composition, the latter is operative to substantially increase the coeilicieni; of friction between the threads themselves without producing a substantial frictional resistance when contacted with other material.

The snagging of hosiery may be generally attributed to a loosening of the thread fibres of the hosiery and the producing of a consequent weakening of the hosiery material. These loose and outstanding fibres are readily caught when moved across a roughened surface with the result that the individual fibres may be pulled completely free `of the threads and the thread thus position is less subject to snagging and the hosiery is thereby given a greatly improvedlife without breaking of the thread at, any part of the hosiery. This action of the composition also substantially improves the sheerness of the material, since the removal of the loose stray fibres substantially increases the size of the interstices in the knitted fabric, thus increasing the transparency of the fabric.

I have found that a zinc resinate compound is completely effective to provide the features and advantages above enumerated. This zinc resinate compound includes materials that have a resin-like feel when rubbed between the fingers and have the property when applied to the fabric fibres of increasing the coeicient of friction between the fibres without sticking of the fibres together and are substantially more viscous than lubricating oils or greases and though the compounds appear vitreous, none are as hard as glass. In use these compositions containing zinc resinate may be dissolved in, or dispersed through a liquid vehicle in which hose may be rinsed, either when the hose is dry or after same has been washed, or the materials with or without their vehicles may be added to the dye bath of the hosiery in the manufacture thereof, or may be incorporated in the materials from which artificial silk thread is formed for use in hosiery material.

In order to test and demonstrate the effectiveness of the various preparations and compounds which may be used in practicing the presen-t invention, I have constructed a test apparatus, as illustrated in Figures 8 and 9 in the drawing, whereby the strength and effectiveness of the preparations may be compared and standardized. This apparatus consists essentially in a pair of inner and outer concentric cylinders 6 and 1 which are mounted for relative lengthwise movement and for measuring of the force in pounds applied in effecting the lengthwise movement of the cylinders. A strip of hosiery 8 to be tested is placed across one end 8 cf the outer cylinder 1 and is held in place thereon by an embracing ring Il, and the inner cylinder 6 moved lengthwise to engage one end i2 thereof against the inner side of the hosiery strip extended across the outer cylinder. A thread at the center of the center cylinder is then severed and the latter cylinder moved ou-twardly against the hose to place the latter under pressure and such pressure increased until the loops unravel or run to one edge of the inner cylinder. To standardize the apparatus I selected an outer cylinder having an inside diameter of 2.225 inches and an outside diameter of 2.357 inches, and an inner cylinder was selected having an inside diameter of 1.725 inches and an outside diameter of 1.850 inches. The necessary pressure applied to the hose in order to cause a running of the stitches or loops to one edge of the inner cylinder is read in terms of pounds net applied to the inner cylinder in placing the hosiery strip under pressure. The number of pounds thus determined is herein referred to as the run load of the hosiery. Thus in the case f untreated hosiery of two or three thread quality, unraveling of the loops to one edge of the inner cylinder will result after severing of a thread of the hosiery at the center of the inner cylinder upon applying of a force of the inner cylinder against the hose of between one to eight ounces.

' 'I'he run load of such untreated hosiery is, thereof, in accordance with the terminology herein, said to be one to eight ounces.

I have found that in order to produce an effective run-inhibiting property in the hosiery that the same must possess a run load characteristic of at least two and one-half pounds. The normal tension of a stocking in the neighborhood of the lmee of the wearer during normal walking and swinging and bending of the leg, corresponds to a run load in the order of one and one-half pounds and frequently exceeds this amount. The stocking in normal wear is frequently subjected to tension corresponding to approximately two and one-half pounds as measured in the above apparatus, and for this reason a minimum run load characteristic of approximately two and one-half pounds is required in order to effectively prevent runs in the hosiery.

' The function of the zinc resinate group of compounds of the present invention when applied to the hosiery is as above indicated, to increase the coeillcient o f friction between the loops of the knitted network forming the hosiery body, whereby the hosiery may be placed under greater tension without an unraveling of the loops, which entails a sliding of the loops across each other in the unfolding process of unraveling. In case of untreated hosiery, the thread will readily slide across itself with the result that the hose need be placed under but a very slight tension in the order of a few ounces as above indicated, in order to effect an immediate and rapid unraveling of the loops after the thread has been severed. When the hose is treated, however, in accordance with the present invention, the individual loops tend to resist slippage of the other loops engaged therewith, while at the same time there is no positive sticking of the loops together. Upon severing of a thread in a strip of hosiery treated with the present compounds and upon placing the hosiery under tension, the loops can be forced to unravel upon applying sufdcient tension, and in unraveling the engaged loops tend to grip and hold together over a substantial portion of the periphery of the thread at the loops. The detaching action of a pair of loops has been illustrated in Figures 2 to 7 in the drawing, wherein the size of the engaged loops is greatly magnifled for clarity and it will be seen that as the loops are drawn apart from each other, they tend at each stage of the separating process to engage a maximum portion of their contacting area. This action is in clear contrast to the unraveling action of untreated hosiery, wherein the loops spring apart from each other and unfold without any appreciable or detectable gripping of the loops with each other. This characteristic of the present group of compounds is of great importance, inasmuch as it provides for a greatly increased tension on the hose without unraveling of the loops and at the same time does not present any outward appearance of stickiness or hardness or roughness, which would otherwise impair the softness and delicacy of the hosiery.

Zinc resinate may be embodied inthe following preparation:

y 'I'he above ingredients are preferably compounded by rst dissolving the zinc resinate in the isopropyl alcohol and the octyl alcohol and thereafter adding the ammonia to this solution.

The water and corn oil soap is mixed together as a separate solution and then added to the first solution. The butoxyethyl stearate is then stirred into the above resulting solution. The basic ingredients here are water, ammonia and zinc resinate. The ammonia functions to form a water soluble complex with the zinc resinate so as to retain the latter in solution. The isopropyl alcohol functions to assist the solubilizing of the zinc resinate and helps form a crystalloid solution, and the octyl alcohol also assists in this function and additionally is used principally to prevent foaming of the ingredients during compounding of the formula and thereafter in rinsing hose in the preparation. The com oil soap functions to hold the resinate in a colloidal state of dispersion as ammonia is lost from the system by evaporation. This oil soap also has the function of acting as a plasticizer to leave the hose soft and pliant and offsets any harsh feel of the hose as might otherwise be left by the zinc resinate deposit. The butoxyethyl stearate acts to increase the sheerness of the hose. The above preparation is preferably used by diluting with water in the proportion of two parts of the preparation to ve or six parts of Water. Threethread hose treated with this preparation tested from three to four pounds run load.

Another form of preparation may be made by colloidally dispersing the zinc resinate without solubilizing the same. Such a preparation provides an important advantage in affording good run load characteristics at very low concentrations of the zinc resinate. This is due to the fact that when the latter substance is applied in a colloidally dispersed form, very little if any penetration of the substance into the hose takes place. Thus substantially all of the zinc resinate is retained at the surface of the hosewhere it is directly effective to prevent runs. An example of such a preparation is the following formula:

Formula 2 Zinc resinate grams-- 10 Acetone -l ml 15 Sodium tetra pyrophospha ml 1 Water ml 30 Ammonia (28%) ml 2% In forming the above preparation, the zinc resinate is first preferably dissolved in the acetone. A solution is then prepared of the last three mentioned ingredients and the first solution stirred into the second. The function of the acetone is to temporarily dissolve the zinc resinate and on addition of the first solution to the second, the zinc resinate dissolves out in ilne particles which promptly, uniformly disperse through the solution by the sodium tetra pyrophosphate. The presence of the ammonia further assists in the forming of ne particles of the zinc resinate. A similar preparation may be made without the rst step of dissolving the zinc resinate and without the use of a solvent. such as acetone, by ilrst grinding the zinc resinate into a fine powder and then adding the powder to a solution of the last three mentioned ingredients and grinding the mixture so formed in a paint mill or a colloid mill or similar type of mill.

In use, the above preparation is added to water in the ratio of one part of the preparation to nine parts of water. Three-thread hose treated with this preparation tested from seven to seven and one-half pounds run load.

'Formula 3 Carbowax 4000" pounds-- 10 Zinc resinate do 30 Ammonia water pints 10 Alcohol (ethyl or isopropyl) -do.. 50 Water do--- 410 'I'his compound is prepared by melting together the carbowax and resinate, and the water containing the ammonia water is slowly added with constant stirring until dispersion is completed. The preparation is then gently heated to expel excess ammonia. The alcohol is added after the mixture cools in order to prevent gelling. This formula provides run loads above 21/2 lbs. Carbowax 4000" is manufactured by Carbide & Carbon Chemical Corporation, and is a polyglycol mixture made by condensing ethylene glycol.

As hereinbefore mentioned, the products of the present invention may be directly incorporated in the fibers of the hose during the manufacture of such ilbre or subsequent thereto but prior to the knitting of the hose, or the products may be applied at some step during the manufacture of the hose, such as in the dye baths. In any of such cases the products of the present invention form an integral part of the completed stocking. I'he present invention is particularly applicable in the manufacture of synthetic fibres such as by `means of the nitrocellulose method (Chardonnet), the cuprammonium method, the viscose method. and the cellulose-acetate method. In such cases various of the aforementioned vitreoresinous products may be added directly to the baths or solutions of the material from which the synthetic fibres are made. I have successfully embodied zinc resinate in a nitro-cellulose solution for increasing the coelcient of friction of the resulting product. Zinc or calcium resinate oolloidally dispersed may be used in the copper oxide and ammonia solution of the cuprammonium process. Similarily these resinates may be used in colloidally dispersed form in the solution of the viscose process. Any of the aforementioned vitreo-resinous products which are soluble in acetone may be directly added to the acetone solution in the cellulose acetate process.

I claim:

1. A run inhibiting preparation for sheer hosiery and having a run load characteristic of at least 21/2 pounds, consisting of zinc resinate, ammonia, water and an organic water-soluble solvent for the zinc resinate consisting of the group of isopropyl alcohol and acetone, said preparation having a sufiicient amount of ammonia to convert the zinc resinate into a water soluble complex.

2. A run inhibiting preparation for sheer hosiery having a run load characteristic of at least 21/2 pounds, consisting of zinc resinate,

water, and ammonia in sumcient amount to convert the zinc resinate into o water soluble complex, and an organic water soluble alcoholic solvent for the zinc resinate, said ingredients being 3. A run inhibiting preparation for sheer hosiery having a. run load characteristic of at least 2% pounds, consisting of. zinc resnabe, water, and ammonia in sumcient amount to convert the zinc resinate into u water soluble complex, and on organic water soluble alcoholic sol= vent for the zincresinate, said ingredients being in about the proportions of:

Zinc resimm: emma" 10 Acetone mi 15 Sodium tetra. pyrophosphgte -..gra.m..- 1 Water ml 30 Ammonia (28%) -ml-- 2% 4. A run-inhibiting prpearation for sheer hosiery having e. run load c teristic of at least 2% pounds consisting of substantially:

Crbowax pounds-.. 10 Zinc resinat do 30 Ammonia. water pints 10 Alcohol do 50 Water dn 410 

